PURPOSE: To achieve complete combustion of smokeless and unharmful exhaust by charging combustibles such as t lime from an upper portion of the furnace and firing them, blowing up air from a lower portion after closing a cover, and mixing and turning principal oxidization heat gas with cyclone gas for secondary combustion.

CONSTITUTION: Coal, charcoal, coke, and combustibles or burned wastes are charged in from a combustibles throw hole 15, and fired, and thereafter a cover is closely tightened. Upper air from a blower fan blows up dynamic pressure air through an air fan iron pipe 23 to combust the entire of a fire grate lower surface with the tip end of the fire grate taken as the center as primary oxidization. Then, normal water is put in and light oil, etc., are put in a combustible gas production chamber 16. Fine pipes are provided parallely to induce the water and the oil which are in turn heated and evaporated through injection to produce fine mist which are further mixed with gas during incomplete combustion and are again blown up to the tip end of the fire grate for complete combustion thereof in a firing tron 7. Thereafter, they are joined with pure heat in a carbon melting reaction chamber to discharge clean heat.